title: [Back up contraception--past, present, future].
authors.forename: D
authors.initials: D
authors.lastname: Tsvetkov
mesh_terms: D044363:Contraception, Postcoital / Q000379:methods* / Q000639:trends*; D003281:Contraceptives, Postcoital / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007434:Intrauterine Devices
chemical_list: D003281:Contraceptives, Postcoital